High-resolution visualization of cochlear cisplatin distribution is essential for understanding its pharmacokinetics and ototoxicity. We employed synchrotron X-ray fluorescence microscopy (XFM) to map platinum (Pt) at sub-micron resolution. Adult male FVB mice received cisplatin (10 mg/kg) through intravenous (i.v.) or intraperitoneal (i.p.) administration. Cochleae were collected on days 1, 7, and 14, cryo-sectioned, and scanned using XFM. Cochlear Pt signal increased progressively through day 14. Notably, i.v. administration led to higher Pt levels than the i.p. route, with the highest increase observed in the organ of Corti on day 14. These results provided the first cell-specific mapping of cochlear Pt distribution and revealed a persistent Pt accumulation long after systemic cisplatin clearance from plasma. Although no significant hearing loss was detected on day 14, the distinct of Pt kinetics between administration routes highlighted critical disconnections in cispla-tin-induced hearing loss between clinical chemotherapy and current preclinical animal models.